The practical performance of pvc heat shrinkable film

The practical performance of pvc heat shrinkable filmRelease time: 2019-10-08 The following points should be paid attention to during the production process of PVC heat shrinkable film: 1. The die should be cleaned accordingly, and no charred plastic should fall into it. What can be found needs to be cleaned up immediately. 2. The paper tube should be aligned accordingly, not long and short. 3. When packing, be careful not to collide and cause quality problems such as edge breakage. 4. Minimize the appearance of surface wrinkles and white pressing lines in the middle, so as not to affect the appearance. 5. The edge material must be cut neatly, and the stretched film that is not cut neatly cannot be shipped as a finished product. The parameters for measuring heat shrinkable film are shrinkage rate, shrinkage tension, and shrinkage temperature. Considering the above three parameters, if you want to obtain a film with a higher shrinkage rate, it is better to use a polymer resin with low crystallinity or low crystallinity. After the amorphous resin is biaxially oriented, although the molecular chains are oriented, no crystallization occurs. After the second preheating, all the oriented chains can shrink, and only the non-crystalline oriented molecular chains will be heated (more Lower processing temperature, shorter processing time) and then shrink; while the molecular chain of oriented crystals needs to be broken to achieve shrinkage, which requires the temperature to be raised near the melting point, and the relaxation time of the molecular chain is longer, and this It is impossible to achieve during the use of shrink film. For the heat shrinkable film made of the same material, the higher the proportion of amorphous area, the greater the shrinkage rate and the greater the shrinkage force. A heat shrinkable film with a larger amorphous area has a lower shrinkage temperature. Previous: Heat shrinkable film has the following six advantages